Aspirator assembly



g- 1939- -L. F. WHITNEY ASPIRATOR ASSEMBLY Filed May 25, 1938 i u ck J SF j Patented Aug. 15, 1939 PATENT OFFICE ASPIRATOR ASSEMBLY Lyman F.Whitney, Cambridge, Mass, assignor, by mesne assignments, to StatorCorporation, a corporation of Rhode Island Application May 25, 1938,Serial No. 209,874

Claims.

This invention relates to an improved aspirator assembly and moreparticularly to an improved nozzle-mounting arrangement for such anassembly. In some respects the present inven- 5 tion provides a furtherdevelopment of or an improvement upon the nozzle-mounting arrangementsdisclosed in my United States Patent No. 1,710,910, dated April 30,1929, and Wescott Patent No. 1,694,087, dated December 4, 1928.

The arrangement disclosed herein may also be employed to particularadvantage with aspirator assemblies of the type disclosed in mycopending application Serial No. 177,749, filed December 2, 1937.

As disclosed in the above-identified Wescott patent, it is highlydesirable to arrange an aspirator nozzle so that it may be accuratelyaligned with the aspirator funnel. Furthermore, as disclosed in both ofthe above-identified patents, it is desirable to arrange the nozzle sothat only a minimum heat flow may take place between the riser pipesupplying hot propellant vapor to the nozzle and the mixing chamber ofthe aspirator assembly. For this purpose, as disclosed in theabove-identified patents, the nozzle itself may be made of thin metal ofrelatively low heat conductivity, and the dome of the mix ng chamberthrough which the nozzle extends also preferably may be made of similarmaterial.

In accordance with this invention, a suitable rod may extend from thenozzle to a supporting bracket, the rod being so arranged that thenozzle may be properly held in alignment by the bracket. For thispurpose I prefer to provide a. bracket of U-shaped form extending fromthe opposite sides of the mixing chamber to a region spaced from thedome of the same, the bight portion of the U-shaped bracket beingdisposed in this region and supporting one end of the rod. The rodpreferably is formed of metal of low heat conductivity, such asstainless steel or nichrome.

The bracket also may be formed of metal of low heat conductivity and maybe provided with openings of substantial size to impede heat flowtherethrough, it being understood that the bracket provides relativelylong paths for the flow of heat.

In the accompanying drawing:

Fig. 1 is a sectional view of an aspirator assembly having anozzle-mounting arrangement in accordance with this invention;

Fig. 2 is an enlarged view of the mixing chamber and nozzle-mountingarrangement on a plane at right angles to that of Fig. 1; and

Fig. 3 is an end elevation of the aspirator assembly showing thenozzle-mounting arrangement.

The accompanying drawing shows an aspirator assembly of the generalcharacter disclosed in my above-identified copending application. Suchan assembly comprises a funnel I with a throat 2 and with a coolingjacket 3. If desired, the funnel may be provided with a plurality offins 4 disposed within the cooling jacket. The assembly is also providedwith a mixing chamber 5 which receives vapor from a supply duct 6. Themixing chamber 5 is provided with a dished end wall or dome I, throughwhich the nozzle 8 may extend. The dome I may be of thin metal of lowheat conductivity, such as nichrome or stainless steel, and may becapable of being distorted slightly to permit adjustment of the angularposition of the nozzle 8.

The nozzle 8, as shown in Fig. 2, is arranged to receive propellantvapor through a tube 9. The connection between the tube and the nozzleis provided with a short tubular extension I!) extending away from thenozzle. Bars ll preferably are welded to the head 5 of the nozzle and.extend outwardly from opposite sides thereof to aiiord supports for theopposite sides of a U- shaped bracket [2. This bracket may be providedby bending a suitable channel into a U- shaped form, as shown. Thischannel preferably is provided with openings l3 of substantial diameterto impede the flow of heat from the head to the bight portion of thebracket; if desired the bracket may be made of metal of low heatconductivity, such as nichrome or stainless steel.

The intermediate part of the bight portion of the bracket I2 is providedwith a central opening IS. A rod ll formed of metal of low heatconductivity, such as nichrome or stainless steel, extends between thenozzle assembly and the bight portion of the bracket. Preferably the rodI! may be considered as being formed in two parts, namely, the rodproper I! and a button l'l in which the end of the rod proper fits witha tight sliding fit. The button has a portion of reduced diameterextending through the opening l6, and a head portion adapted to engagethe outer surface of the bight portion of bracket 12. It will beunderstood that both the button I1 and the rod proper I! are preferablyformed of metal of low heat conductivity. The inner end of rod I!preferably is welded to a metal plug I9, which fits within and is weldedto the short tubular extension In of the nozzle assembly.

When the parts are first assembled they may be arranged in the mannerwhich has been described, it being noted that the opening I6 is somewhatlarger than the corresponding portion of the bushing ll' which extendstherethrough, so that the angular position of the rod I! is then onlyapproximately determined. lhereafter, the nozzle 8 may be brought intoaccurate alignment with the funnel l by means of a suitable aligningbar, as more fully disclosed in the copending application of Russell A.Gulick, filed on even date herewith. After the nozzle is thus broughtinto accurate alignment with the funnel, the enlarged portion of thebushing i l is secured to the bight portion of the bracket 12 by brazing26.

It is evident that the present invention affords a simple and effectivearrangement for holding an aspirator nozzle in accurate alignment withan aspirator funnel, and. that such an arrangement is particularlyadvantageous in avoiding unnecessary heat losses. The bracket l2 affordsrelatively long paths of low heat-conductivity extending away from thehead of the aspirator assembly, while the rod i? also affords a path oflow heat-conductivity and of relatively small cross section. Theprovision of the U-shaped bracket [2 affords symmetrical supportingmeans for the rod so that heat expansion does not tend to cause movementof the nozzle out of align ment with the funnel.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claims.

I claim:

1. An aspirator assembly comprising a mixing chamber, a funnel extendingfrom the mixing chamber, a duct to supply fluid to the mixing chamber,said mixing chamber having an end wall, a nozzle secured. to said wallin alignment with said funnel, a duct for supplying vapor to saidnozzle, a rod extending from said nozzle, a bracket extending from saidmixing chamber and having a portion remote therefrom to which the rod isfixed, thereby to hold the nozzle in alignment with the funnel, said rodbeing formed of metal of low heat conductivity to impede the flow ofheat away from the nozzle.

2. An aspirator assembly according to claim 1, wherein the bracket is aU-shaped metal member connected to opposite sides of the mixing chamberand having its bight portion connected to the rod.

3. An aspirator assembly comprising a mixing chamber, a funnelextendingfrom the mixing chamber, a duct to supply fluid to the mixingchamber, said mixing chamber having an end wall, a nozzle secured tosaid wall in alignment with said funnel, a duct for supplying vapor tosaid nozzle, a rod extending from said nozzle substantially in alignmentwith said funnel, a U- shaped bracket connected to opposite sides of themixing chamber and having its bight portion spaced from said chamber,said rod being secured to the bight portion of said bracket.

4. An aspirator assembly comprising a mixing chamber, a funnel extendingfrom the mixing chamber, a duct to supply fluid to the mixing chamber,said, mixing chamber having an end wall, a nozzle secured to said wallin alignment with said funnel, a duct for supplying vapor to saidnozzle, a rod extending from said nozzle substantially in alignment withsaid funnel, a U-shaped bracket connected to opposite sides of themixing chamber and having its bight portion spaced from said chamber,said rod being secured to the bight portion of said bracket, saidbracket being formed of metal of low heatconductivity to impede the flowof heat away from the nozzle.

5. An aspirator assembly comprising a mixing chamber, a funnel extendingfrom the mixing chamber, .a duct to supply fluid to the mixing chamber,said mixing chamber having an end wall, a nozzle secured to said wall inalignment with said funnel, a duct for supplying vapor to said nozzle, arod extending from said nozzle substantially in alignment with saidfunnel, a U- shaped bracket connected to opposite sides of the mixingchamber and having its bight portion spaced from said chamber, said rodbeing secured to the bight portion of said bracket, both said rod andsaid bracket being formed of metal of low heat conductivity to impedethe flow of heat away from the nozzle.

LYMAN F. WHITNEY.

